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Correct answer
B. Spiral Galaxy
Explanation
Spiral Galaxy is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
C. 57.9 million km
Explanation
57.9 million km is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
B. Cobalt
Explanation
Cobalt is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
A. convex lens
Explanation
convex lens is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
C. they fall with that ultimate velocity, which are different for different droplets
Explanation
Any mass is attracted to the Earth by the pull of gravity. Gravity accelerates all objects towards the ground at a specific rate. Without any other forces present, the speed of an object in free fall will increase the farther or longer it falls. In general the air resistance on an object depends upon several variables. First, it depends upon the shape of the object. Its shape determines the object’s drag coefficient: the more aerodynamic the shape, the less drag. Second, it depends upon the size of the object; specifically the cross-sectional area presented to the airflow (perpendicular to the direction of travel). And lastly, it depends upon the speed of the object. At low speeds the object’s resistance is directly proportional to speed, and at higher speeds the object’s resistance is proportional to its speed squared. Most objects falling through the air would be considered to be moving at a higher speed, even though that speed might not be great compared to some velocities.
Correct answer
A. Ginger
Explanation
Ginger is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
E. Sodium Chloride
Explanation
Sodium Chloride is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
D. 248 years
Explanation
Pluto takes 248 Earth years to make one revolution around the sun. That means one year on Pluto is about 248 Earth years.
Correct answer
B. Mars
Explanation
Mars is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.
Correct answer
B. Carbon dioxide
Explanation
Carbon dioxide is the correct answer. Review the question and compare it with the other choices to remember this fact for future exams.